Their main handicap is that their conversion rate is very low, of just 3% (10-20% in conventional ones, some recent advances may be even more efficient) but their extremely low production cost makes them still very interesting.
The manufacturing cost is 1/100,000 of the one with glass substrates, 1/500 ~ 5,000 of the one with plastic.
In other words: ridiculously cheap!
This technological advance was achieved by Associate Professor Nogi, from Osaka University (Japan).
It is more and more clear that solar energy (along with other renewable sources) is the immediate future. Germany, for example, has greatly benefited in many aspects from investing in this and it can only get better in the future. Instead the prospects of oil and nuclear are very gloomy, while coal is the main cause of China's horrible pollution troubles, for example (never mind its climate warming impact).